AIMROCK 5-Pack 48P RC Motor Pinion Gears Set – 22T to 26T, Hardened Steel, 3.175mm Bore

This AIMROCK 5-pack pinion gear set delivers five common tooth counts—22T, 23T, 24T, 25T, and 26T—all with a 48-pitch and a 3.175mm (1/8 inch) bore. Designed for 1/10 scale RC cars, boats, and planes, each gear is machined from hardened steel to handle high-torque loads. The set also includes five grub screws and a steel hex key for installation.

Why must these pinion gears only be used with steel spur gears?

The hardened steel construction of these pinions is much harder than plastic or aluminum. Running them against a softer spur gear will quickly wear down or chip the spur gear teeth, leading to poor mesh and eventual failure. For best performance and longevity, pair these 48-pitch pinions with a steel spur gear of the same pitch.

Which RC vehicles are compatible with these pinions?

These gears fit any RC car, boat, or plane that uses a 48-pitch spur gear and a motor shaft diameter of 3.175mm (1/8 inch). They are especially common in 1/10 scale touring cars, buggies, and short-course trucks. Before ordering, confirm your spur gear’s pitch (must be 48P) and shaft size.

Gear set details at a glance

Frequently asked questions

Can I use these with plastic or aluminum spur gears?
No. The manufacturer explicitly warns against it because the hardened steel pinions will damage softer spur gears. Always use a steel spur gear.

What is the inner diameter of these pinions?
All five gears have a 3.175mm (1/8 inch) bore, which fits standard RC motor shafts of the same size.

How do I change the speed of my RC car with these gears?
Swap to a higher tooth count (e.g., 26T) for higher top speed and lower acceleration, or a lower tooth count (e.g., 22T) for quicker acceleration and lower top speed. The five included sizes let you tune your gearing for different tracks or conditions.

Does the set include the mounting screws?
Yes, it comes with five grub screws (set screws) and one steel hex key to tighten them.